1. Field of the Invention
The present invention relates to a wood fiber board that is used in vehicle interiors, building materials, furniture and the like.
2. Description of the Related Art
Conventionally, wood is made into wood chips using a crusher or the like, the obtained wood chips are steamed and are fibrillated using a refiner or the like, to produce a fiber board out of the wood fibers. For instance, Japanese Patent Application Publication No. 2001-3300 discloses a method of manufacturing a wood fiber board by forming a sheet out of a starting material slurry in which wood fibers are dispersed, dewatering the formed sheet by suction, using a cylinder sheet-forming machine, followed by forming and drying, to produce thereby a wood fiber board.
The production method set forth in Japanese Patent Application Publication No. 2001-3300 requires a binder for binding fibers to each other. Japanese Patent Application Publication No. 2001-3300 discloses, starch thickeners, phenolic resins, melamine resins, urea resins and the like as examples of binders. Among those, phenolic resins have been used from the viewpoint of strength and water resistance.
However, concerns about the odor and volatile organic compounds released by phenolic resins have become a concern against the background of growing environmental awareness in recent years. Desirably, therefore, wood fiber boards should contain no phenolic resins.
The applicants had already filed Japanese Patent Application Publication No. 2010-121058 relating to a phenolic resin-free wood fiber board.
The wood fiber board of Japanese Patent Application Publication No. 2010-121058 is produced using an acrylic resin and an epoxy resin containing no bisphenol A, instead of using a phenolic resin. Therefore, the board has no phenol odor, and the release of volatile organic compounds is extremely small.
The wood fiber board of Japanese Patent Application Publication No. 2010-121058, however, utilizes two types of resin, namely an acrylic resin and an epoxy resin containing no bisphenol A, as binders, and requires moreover paraffin in order to enhance water resistance. The board is thus troublesome in terms of equipment and operations, which should be streamlined.